A1-segment aneurysms: Management protocol based on a new classification

Abstract

AI-segment aneurysms have unique properties: rupturing of small-sized aneurysms; multiplicity; undetectable on initial imaging; frontal lobar/intraventricular bleeding; origin from main trunk and not bifurcating points; neck obscuration by AI-trunk; close proximity to perforators; and, associated AI-segment and ACA anomalies. A new classification identifies surgical difficulties inherent in different sites of origin of A1-aneurysms.

Mid A1 blister aneurysm presenting with subarachnoid hemorrhage: Case report and review

“…Temporary clips should be used judiciously to avoid ACA infarction. [ 16 ] As in our case, if bilateral A1s are equal in caliber and the Acomm patent, then vessel sacrifice may be well tolerated.…”

“…One study classifying A1 lesions found that these lesions can rupture at small sizes, can be difficult to detect, multiple, and presentation can include intraventricular hemorrhage. [ 16 ] Blister aneurysms can be responsible for angiography-negative SAH and may not be detected until the second or third angiograms. [ 5 6 ] In addition, CT angiography may be useful in diagnosis if DSA is negative multiple times.…”

“…Opening of the interhemispheric fissure or resection of the overlying gyrus rectus can sometimes help give space if needed. [ 16 ] Small lesions on the back of the artery such as ours are the most difficult to treat. Temporary clips should be used judiciously to avoid ACA infarction.…”

Prognostic Factors for Anterior Cerebral Artery Aneurysms: A Single-Center Series

“…Key Words: Anterior cerebral artery aneurysm, intracranial aneurysm, risk factors I ntracranial aneurysm is a cystic bulge in the wall of the intracranial artery, which is the first cause of spontaneous subarachnoid hemorrhage (SAH), ranging from 3.6% to 6.0%. 1,2 Anterior cerebral artery aneurysms (ACAAs) are known for their rarity, comprising ~5% of all intracranial aneurysms, [3][4][5][6] and only a few cases have been reported. The anterior cerebral artery is the final branch of the internal carotid artery, which enters the cerebral column above the optic chiasm and extends laterally inside the cerebral hemisphere.…”

“…Therefore, their frequent proximity to perforators, location behind the parent artery, or adherence to surrounding structures, making difficult to surgery. 4,5,7 As a result, the incidence of surgeryrelated complications and sequelae is relatively high. In recent years, some clinical prognostic factors such as age, Hunt-Hess grade, operation timing, the location of aneurysms, irregular shape, and size have been reported.…”